In a biochemistry lab students carry out a SDS-PAGE gel experiment on a protein witha known molecular weight of 45 kDa. Unfortunately, each student group made a different mistake during the protocol. Consider each mistake and explain how the mistake would alter the results for that group.
A. The sample was not mixed with sample buffer prior to loading on the gel.
B. The sample was mixed with sample buffer that did not contain SDS prior to loading on the gel.
C. The sample was mixed with sample buffer that did not contain a reducing agent prior to loading on the gel.
D. The student failed to add the protein to the sample buffer.
E. The scientist did not include a molecular weight marker standard on the gel.
F. The students attached the anode of the power supply to the bottom of the gel and the cathode to the top of the gel.
G. The gel was stopped when the bromphenol blue was about 1cm from the top of the gel.
H. The gel was never placed into the stain.